President Trump finally made it to Vietnam — but he did it using a ton of taxpayer dollars … and got a whole lot of nothin’ out of it from North Korea.

TMZ did some digging on the cost of Trump’s second summit with Kim Jong-un in Hanoi, and turns out it was at least $1.3 million … much of which went toward putting Americans up for a couple of nights and making sure they were cozy.

According to federal procurement docs — obtained by TMZ — lodging alone for Trump and co. during the two-day summit — which wrapped Thursday without a deal on nukes or sanctions — ran Uncle Sam upwards of $632k between 3 hotels and miscellaneous costs.

The State Dept. foot the majority of that lodging bill, including a separate $157k for lodging at the Melia Hanoi Hotel — where Kim Jong-un stayed and where the American press corp was staying as well … before getting booted by Kim’s camp.

According to reports, Kim became uneasy with the American press in such close proximity … so they were ultimately moved to a new hotel.

But, wait … there’s more!!!

The conference rooms alone where Trump and Kim couldn’t come to terms cost $316k, and things like lights, stereo systems, drapes and awnings ran about $100k all together. The Dept. of Defense dropped about $60k for leased internet lines.